Help getting memory into my Array and formated properly

$PCs = Get-Content -Path "P:\scripts\PCs.txt"

$local = Get-Credential administrator
$results = @{}
$results = foreach ($PC in $PCs)
{
    if (Test-Connection -ComputerName $PC -Count 1 -Quiet)
    {
        Write-Verbose "Working on $PC"
        $bios = Get-WmiObject Win32_BIOS -ComputerName $PC -Credential $local
        $Proc = Get-WmiObject Win32_processor -ComputerName $PC -Credential $local | Select-Object -First 1
        $memory = Get-WmiObject Win32_physicalmemory -ComputerName $PC -Credential $local | Select *
        $system = Get-WmiObject Win32_ComputerSystem -ComputerName $PC -Credential $local
        $os = Get-WmiObject Win32_OperatingSystem -ComputerName $PC -Credential $local
        $Networks = Get-WmiObject Win32_NetworkAdapterConfiguration -ComputerName $PC -Credential $local | ? {$_.IPEnabled}
 $logonServer = Get-WmiObject -Class win32_ntdomain -Filter "DomainName = 'Corp'" -ComputerName $pc -Credential $local
 $Mem = [math]::round($PC.TotalPhysicalMemory/1024/1024/1024, 0)

        [PSCustomObject]@{
            "PC Name" = $os.csname
            InstallDate = $os.ConvertToDateTime($os.installDate)
            "OS Version" = $os.Caption
     OSArchitecture =$os.OSArchitecture
     UserName = $system.UserName
     Domain = $system.Domain
     Manufacturer = $system.Manufacturer
     Model = $system.Model
     Memory = $System.TotalPhysicalMemory | where-Object {$_.freespace / 1MB}
     SerialNumber = $Bios.SerialNumber
            "Processor Name" = $proc.Name
            "Processor Manufacturer" = $proc.Manufacturer
            "Processor Max Clock Speed" = $proc.MaxClockSpeed
     "CPU hardware 32 or 64" = $Proc.AddressWidth
            IPAddress = $networks.IpAddress[0]
            SubnetMask = $Networks.IPSubnet[0]
            DefaultGateway = $Networks.DefaultIPGateway | Where-Object {$_}
            "DNS Servers" = $Networks.DNSServerSearchOrder | Where-Object {$_}
     "Logon Server" = $LogonServer.DomainControllerName
     Mem = $system.[math]::round($PC.TotalPhysicalMemory/1024/1024/1024, 0)
        }
    }
 }

$results | format-list

I found this example and tested and works fine and memory shows as 8 GB

$x = read-host -prompt "Please enter the machine name: " 

$colItems = get-wmiobject -class "Win32_ComputerSystem" -namespace "root\CIMV2" -computername $x

foreach ($objItem in $colItems){
$displayGB = [math]::round($objItem.TotalPhysicalMemory/1024/1024/1024, 0)
write-host "Total Physical Memory: " $displayGB "GB"
write-host "Model: " $objItem.Model
}

$colItems = get-wmiobject -class "Win32_Processor" -namespace "root\CIMV2" -computername $x
foreach ($objItem in $colItems){
write-host "System Name: " $objItem.SystemName
}